8-(t-Butyldimethylsilyloxy)-1-octyne → 4-[8-(t-Butyldimethylsilyloxy)-1-octynyl]-4-hydroxy-7-methoxy-3-(4-methoxyphenyl)-3-methylthiochroman

Participants

Reaction Conditions

Reaction Steps

8-(t-Butyldimethylsilyloxy)-1-octyne (12 g, 49.9 mmol) was dissolved in dry tetrahydrofuran (150 ml) under argon atmosphere and then cooled to −78C. 2.5M n-Butyllithium (18 ml, 44.9 mmol) was added dropwise thereto, and the mixture was warmed to −10° C. and stirred for 1 hour and then cooled to −78° C. 7-Methoxy-3-(4-methoxyphenyl)-3-methylthiochroman-4-one (860 mg,2.9 mmol) was added portionwise and then warmed to room temperature and stirred for 1.5 hour. The mixture was quenched by water. The reaction solvent was evaporated off, then the residue was dissolved in ethyl acetate, which was washed with water. The organic solvent was dried over anhydrous magnesium sulfate and removed by evaporation under vacuum. This product was purified by column chromatography on silica gel, eluting with 10% ethyl acetate in n-hexane. After removal of the solvent, 14 g of the title compound was obtained as colorless oil. (yield: 99.3%)

Provenance & Evidence